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卷五十六 志第八: 曆五

Volume 56 Treatises 9: Calendar 5

Chapter 56 of 元史 · History of Yuan
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1
Calendar 5 — Gengwu Origin Calendar, Part One.
2
The epoch reckons the high origin at gengwu, at an interval from Taizu's gengchen year of 20,275,270 years beyond the count; to examine antiquity upward, subtract one count per year; to verify the future downward, add one count per year. Stepwise computation: qi and lunation.
3
Day unit: 5,230. Tropical year length: 1,910,024 parts. Universal remainder: 27,424 parts. Synodic-month constant: 154,445 parts.
4
Universal intercalation: 56,884 parts. Year divisor: 365 days, remainder 1,274 parts. Synodic-month divisor: 29 days, remainder 2,775 parts. Qi divisor: 15 days, remainder 1,142 parts 60 seconds.
5
Full-moon divisor: 14 days, remainder 4,002 parts 45 seconds. Quarter-moon divisor: 7 days, remainder 2,001 parts 22½ seconds. Extinction limit: 4,087 parts 30 seconds. New-moon void parts: 2,455.
6
Ten-day cycle: 313,800 parts. Era divisor: 60. Second divisor: 90. To find the winter solstice of the civil year.
7
滿
Set the accumulated years since the gengwu high origin, multiply by the tropical year length, and obtain the universal accumulated parts; divide by the ten-day cycle and discard the quotient; with the remainder, reduce by the day unit to obtain days, and what does not fill a day becomes the remainder; count from renxu beyond the counting rod, and the major and minor remainders of the sought civil-year winter solstice are obtained. (First apply the inner difference to add or subtract from the universal accumulated parts, then proceed with the calculation. (The method for finding the inner difference is given in full in the 《Lunar Motion》 section.)
8
To find the next solar term.
9
滿
Set the major and minor remainders of the civil-year winter solstice and add the qi divisor and its remainder cumulatively; when seconds fill the second divisor, carry to parts, and when parts fill the day unit, carry to days; the day and remainder in parts and seconds of the next solar term are thereby obtained. To find the mean new moon of the civil year.
10
滿 滿
Set the universal accumulated parts, divide by the synodic-month constant and take the remainder as the intercalation remainder; subtract this from the universal accumulated parts to obtain the new-moon accumulated parts; divide by the ten-day cycle and discard the quotient; with the remainder, divide by the day unit to obtain days, and what remains becomes the fractional remainder; the major and minor remainders of the sought civil-year mean new moon are thereby obtained.
11
To find the quarter and full moons and the next new moon.
12
Set the major and minor remainders of the civil-year mean new moon and add the quarter-moon divisor cumulatively; the mean days and remainders in seconds for each quarter moon, full moon, and subsequent new moon are thereby obtained. To find the extinction day.
13
滿
Set the minor remainder of the constant qi for a term that bears an extinction; if it reaches the extinction limit or above, that term has an extinction; multiply by the second divisor and include the seconds, then subtract the result from 477,556; with the remainder, divide by 6,856; add the quotient to the major remainder of the constant qi, count from renxu beyond the counting rod, and the extinction day is obtained.
14
To find the annihilation day.
15
滿
Set the minor remainder of the new moon that bears an annihilation, (when the mean new moon's minor remainder does not fill the new-moon void parts.) multiply by six and divide by 491; add the quotient to the mean new moon's major remainder to obtain the annihilation day. Stepwise computation: hexagrams, hou, and issuing-and-gathering. Hou divisor: 5, remainder 380 parts 80 seconds.
16
Hexagram divisor: 6, remainder 457 parts 6 seconds. Zhen divisor: 3, remainder 228 parts 48 seconds. Second divisor: 90. Double-hour divisor: 2,615.
17
Half double-hour divisor: 1,307½. Quarter-hour divisor: 313 parts 80 seconds. Double-hour quarter-hours: 8, 104 parts 60 seconds. Half double-hour quarter-hours: 4, 52 parts 30 seconds.
18
Second divisor: 100. To find the seventy-two hou.
19
Set the major and minor remainders of the solar term and designate them as the first hou; add the hou divisor cumulatively to obtain the second hou and the final hou. To find the sixty-four hexagrams.
20
Set the major and minor remainders of the mid-term and designate them as the duke hexagram; add the hexagram divisor cumulatively to obtain the lord hexagram; add again to obtain the inner hou hexagram; add the zhen divisor to reach the beginning of the solar term, which is the outer hou hexagram; add the zhen divisor again to obtain the great officer hexagram; add the hexagram divisor again to obtain the minister hexagram.
21
To find the day when Earth holds royal sway: subtract the zhen divisor from the major and minor remainders of the mid-terms of the four seasons, and the day of Earth's royal sway is obtained. To find the issuing and gathering.
22
Set the minor remainder, multiply by six, and divide by the double-hour divisor to obtain the double-hour count; with the remainder, divide by the quarter-hour divisor to obtain quarter-hours; count from midnight beyond the counting rod, and the double-hour, quarter-hour, and parts of the time-of-day are obtained. (If the half double-hour divisor is added, count from the beginning of zi.) To find the hexagrams and hou for the twenty-four solar terms.
23
(The tables below are omitted.) Stepwise computation: solar motion. Circuit-of-heaven parts: 1,910,092 parts 98 seconds. Annual precession: 68 parts 98 seconds.
24
Second divisor: 100. Circuit of heaven: 365 degrees, 25 parts 67 seconds. Quadrant limit: 91 degrees 31 parts 9 seconds. Parts-and-seconds divisor: 100.
25
Daily accumulated solar degrees: expansion and contraction for the twenty-four qi. (Table omitted.) Mid-accumulation and lunar wanings and waxings for the twenty-four qi. (Table omitted.)
26
To find the daily expansion and contraction and lunar waning and waxing.
27
For each term, set its increase-decrease rate, (To find expansion and contraction, use the increase-decrease of expansion and contraction; (to find waning and waxing, use the increase-decrease of waning and waxing.) multiply by six and divide by the quadrant limit to obtain the mid-rate for that term; subtract it from the next term's mid-rate to obtain the combined difference; take half the combined difference and add or subtract it from the term's mid-rate to obtain the general rate at the origin and end, (After a solstice, add at the beginning and subtract at the end; (after an equinox, subtract at the beginning and add at the end.) again set the combined difference, multiply by six, divide by the quadrant limit, and obtain the daily difference; halve it and add or subtract from the general rates at beginning and end to obtain the fixed rates at beginning and end; (After a solstice, subtract at the beginning and add at the end; (after an equinox, add at the beginning and subtract at the end.) add or subtract the daily difference cumulatively from the fixed rate at the term's beginning to obtain each day's increase-decrease parts; (After a solstice, subtract; (after an equinox, add.) for each day, add or subtract the daily increase-decrease parts from the term's expansion-contraction and waning-waxing values to obtain the daily expansion-contraction and waning-waxing. (For the term before each equinox that lacks a following rate to form the combined difference, use the previous term's combined difference instead.)
28
To find the solar term entered by the mean new moon, quarter moon, and full moon.
29
滿 滿 便
Set the civil-year intercalation remainder, divide by the day unit to obtain days, and what does not fill a day becomes the remainder. If it reaches the qi divisor or below, subtract it from the qi divisor to obtain entry into the Great Snow term; if above, discard one qi divisor; with the remainder also subtract the qi divisor to obtain entry into the Lesser Snow term; the day and remainder of the civil-year mean new moon's entry into a solar term are thereby obtained. Add the quarter-moon divisor cumulatively and, when it fills the qi divisor, discard the quotient to obtain the day and remainder of entry into the next term for the quarter and full moons; by the same addition the day and remainder of the next new moon's entry into a term are obtained. (This directly gives the mid-term entry for new and full moons.)
30
To find the daily increase-decrease, expansion-contraction, and waning-waxing.
31
Add or subtract the daily difference from the term's initial increase-decrease rate to obtain the daily increase-decrease rate; accumulate in sequence the increase-decrease applied to the term's expansion-contraction and waning-waxing totals to obtain the daily expansion-contraction and waning-waxing accumulations. To find the fixed waning-waxing number for the mean new moon, quarter moon, and full moon at their entry into a term.
32
便 宿
Multiply each sought entry-into-qi minor remainder by that day's increase-decrease rate and divide by the day unit; add or subtract the result from the waning-waxing accumulation below to obtain the fixed number. (This directly gives the fixed waning-waxing number for the mid-term new moon, quarter moon, and full moon.) Degrees of the equatorial lodges.
33
宿
Dipper: 25 degrees; Ox: 7 degrees. (small) Girl: 11 degrees. (small) Emptiness: 9 degrees. (67 small seconds) Rooftop: 15½ degrees; Room: 17 degrees; Wall: 8 degrees. (large) At right: the seven northern lodges, 94 degrees. (67 seconds)
34
西宿
Legs: 16½ degrees; Bond: 12 degrees; Stomach: 15 degrees; Hairy Head: 11 degrees. (small) Net: 17 degrees. (small) Turtle Beak: ½ degree; Three Stars: 10½ degrees. At right: the seven western lodges, 83 degrees.
35
宿
Well: 33 degrees. (small) Ghost: 2½ degrees; Willow: 13 degrees. (large) Star: 6 degrees. (large) Extended Net: 17 degrees. (small) Wings: 18 degrees; Axletree: 17 degrees. At right: the seven southern lodges, 109 degrees. (small)
36
宿
Horn: 12 degrees; Neck: 9 degrees. (small) Base: 16 degrees; Room: 5 degrees. (large) Heart: 6 degrees. (small) Tail: 19 degrees. (small) Winnowing Basket: 10½ degrees. At right: the seven eastern lodges, 79 degrees. To find the winter solstice equatorial solar degree.
37
滿退 宿滿宿宿 西
Set the universal accumulated parts and divide by the circuit-of-heaven parts; with the remainder, divide by the day unit to obtain degrees, and reduce what does not fill a degree into parts and seconds; with 100 as divisor, count from 6 degrees beyond Emptiness in the equatorial lodges and discard full lodges; the remainder gives the equatorial lodge, degrees, and parts-seconds of the sun at the winter solstice of the sought year with time-of-day. (For places east and west of Xanadu, first apply the inner difference to add or subtract from the universal accumulated parts.)
38
To find the equatorial solar degrees at the spring equinox, summer solstice, and autumn equinox.
39
滿宿宿 宿
Set the equatorial solar degree at the civil-year winter solstice with time-of-day, add the quadrant limit cumulatively, and when it fills the equatorial lodge sequence discard the quotient; the lodge, degrees, and parts-seconds of the sun at the spring equinox, summer solstice, and autumn equinox with time-of-day are thereby obtained. To find the accumulated equatorial lodge degrees after the four cardinal points.
40
宿 宿宿 宿
Set the full degree of the equatorial lodge at each cardinal point, subtract the equatorial solar degree and parts-seconds at that cardinal point, and the remainder is the degrees after the interval; add the equatorial lodge degrees cumulatively to obtain the accumulated equatorial lodge degrees and parts-seconds after each cardinal point. To find whether the accumulated equatorial lodge degrees fall within the beginning or end limit.
41
宿 宿
Inspect the accumulated equatorial lodge degrees and parts after a cardinal point; if they are 45 degrees 65 parts 54½ seconds or below, they fall within the beginning limit; if above, subtract from the quadrant limit; the remainder falls within the end limit. To find the ecliptic degrees of the twenty-eight lodges.
42
宿 滿滿 宿宿 宿 宿宿 宿
Set the beginning- or end-limit degrees and parts for the equatorial lodge after a cardinal point and subtract 101 degrees; multiply the remainder by the beginning- or end-limit degrees and parts, carry when needed, and when the product fills 100 convert to parts, and when parts fill 100 convert to degrees; after a solstice subtract from, and after an equinox add to, the accumulated equatorial lodge degrees to obtain the lodge's accumulated ecliptic degrees; subtract the previous lodge's accumulated ecliptic degrees, (For the lodges at the four cardinal points, first add the quadrant limit, then subtract the previous lodge.) to obtain that lodge's ecliptic degrees and parts. (The parts are rounded to the nearest large, half, or small degree.)
43
宿
Degrees of the ecliptic lodges.
44
宿
Dipper: 23 degrees; Ox: 7 degrees; Girl: 11 degrees; Emptiness: 9 degrees. (67 small seconds) Rooftop: 16 degrees; Room: 18 degrees. (small) Wall: 9½ degrees. At right: the seven northern lodges, 94 degrees. (67 seconds)
45
西宿
Legs: 17 degrees. (large) Bond: 12 degrees. (large) Stomach: 15½ degrees; Hairy Head: 11 degrees; Net: 16½ degrees; Turtle Beak: ½ degree; Three Stars: 9 degrees. (large) At right: the seven western lodges, 83 degrees. (large)
46
宿
Well: 30½ degrees; Ghost: 2½ degrees; Willow: 13 degrees. (small) Star: 6 degrees. (large) Extended Net: 17 degrees. (large) Wings: 20 degrees; Axletree: 18½ degrees. At right: the seven southern lodges, 109 degrees. (small)
47
宿
Horn: 12 degrees. (large) Neck: 9 degrees. (large) Base: 16 degrees. (small) Room: 5 degrees. (large) Heart: 6 degrees; Tail: 18 degrees. (small) Winnowing Basket: 9½ degrees. At right: the seven eastern lodges, 78 degrees. (small)
48
宿 宿
The ecliptic lodge degrees given above are fixed by calculation according to the annual precession in the present calendar. As when examining antiquity above and verifying the future below, one must rely on annual precession: for each shift of one degree, derive the lodge degrees of that epoch by the prescribed method; only then can the seven luminaries be stepped and their positions known. To find the ecliptic solar degree at the civil-year winter solstice with time-of-day.
49
滿滿
From the equatorial solar degree and parts-seconds at the winter solstice with time-of-day, subtract 101 degrees; multiply the remainder by that equatorial degree and its parts-seconds, carry when needed, and when the product fills 100 convert to parts and when parts fill 100 convert to degrees—this is the yellow-red difference; Subtract this from the equatorial solar degree and parts-seconds at the winter solstice with time-of-day to obtain the ecliptic solar degree and parts-seconds at the civil-year winter solstice of the sought year with time-of-day.
50
To find the ecliptic solar degree with time-of-day for each of the twenty-four solar terms.
51
宿宿 宿宿
Set the yellow-red difference at the winter solstice sun's position for the sought year, subtract the next year's yellow-red difference, multiply the remainder by the number of the term sought, and divide by twenty-four; Add the result to that term's mid-term accumulated degrees and rounded parts; apply the term's first-day expansion-contraction value—add when in surplus, subtract when in contraction—and add this to the ecliptic solar degree at the winter solstice with time-of-day; discard full lodges in lodge sequence to obtain each term's ecliptic lodge, degrees, and parts-seconds of the sun's motion with time-of-day. (If the fractional parts of the equatorial lodge degree at the winter solstice with time-of-day fall below the annual precession value, add the previous lodge's full degree before computing the yellow-red difference; compute the remainder by the prescribed method.)
52
To find the ecliptic solar degree before dawn and at midnight for each solar term and each day.
53
滿退
Set aside the minor remainder of its constant qi and multiply it by that term's first-day increase-decrease rate, (Increase-decrease of expansion and contraction.) Reduce by ten thousand; where the rate is to increase, add when in surplus and subtract when in contraction; where it is to decrease, subtract when in surplus and add when in contraction; divide the auxiliary value by the day unit to obtain degrees, and reduce the remainder into parts and seconds; subtract this from the term's ecliptic solar degree with time-of-day to obtain the ecliptic solar degree before dawn and at midnight on the first day of that term. Add one degree for each day, multiply by ten thousand, and then by each day's increase-decrease number, (Increase-decrease of expansion and contraction.) where the rate is to increase, add when in surplus and subtract when in contraction; where it is to decrease, subtract when in surplus and add when in contraction—to obtain each day's ecliptic solar degree and parts-seconds before dawn and at midnight.
54
To find the ecliptic solar degree at noon for each day.
55
滿滿宿
Set 10,000 parts and add or subtract the daily increase-decrease number for the day within the term, (Where increasing, add when in surplus and subtract when in contraction; (where decreasing, subtract when in surplus and add when in contraction.) Halve it; when the result fills 100 convert to parts and what does not fill becomes seconds; add this to that day's ecliptic solar degree before dawn and at midnight to obtain the ecliptic lodge, degrees, and parts-seconds of the sun's motion at noon that day.
56
To find the accumulated ecliptic solar degree at noon for each day.
57
From the ecliptic solar degree at a solstice with time-of-day, take the interval to the sought day's ecliptic solar degree at noon as the accumulated ecliptic solar degrees and parts-seconds after entry into the solstice. To find whether each day's noon ecliptic degree falls within the beginning or end limit.
58
滿
View the accumulated ecliptic degrees after a solstice: if at or below 43° 12′ 87″, this is within the beginning limit; If above, subtract from the quadrant limit; the remainder falls within the end limit. When the accumulated degrees fill the quadrant limit, discard the quotient to obtain the accumulated ecliptic degrees after an equinox; If at or below 48° 18′ 21″, this is within the beginning limit; If above, subtract from the quadrant limit; the remainder falls within the end limit.
59
To find the equatorial solar degree at noon for each day.
60
Take the accumulated ecliptic degree at the sought noon and the degrees and parts-seconds within the beginning limit after a solstice or the end limit after an equinox; advance three places, add 202,050 plus a fractional small amount, extract the square root and divide; subtract 449½ from the result; if within the beginning limit, add directly to the equatorial solar degree at the solstice and count off in lodges; If within the end limit, subtract from the quadrant limit and add the remainder to the equatorial solar degree at an equinox and count in lodges to obtain the equatorial solar degree at each noon.
61
Take the accumulated ecliptic degree at the sought noon and the degrees and parts-seconds within the end limit after a solstice or the beginning limit after an equinox; advance three places, subtract from 303,050 plus a fractional small amount, extract the square root and divide; subtract 550½ from the result; if within the beginning limit, add the remainder after subtraction directly to the equatorial solar degree at an equinox and count off in lodges; If within the end limit, subtract from the quadrant limit and add the remainder to the equatorial solar degree at a solstice and count in lodges to obtain the equatorial solar degree at each noon.
62
宿
Ecliptic palace-entry degrees for the sun's twelve regions: beyond 13° 39′ 59″ in Rooftop the sun enters Wei's territory in Zouzi, with the celestial mark at hai. Beyond 2° 35′ 85″ in Legs the sun enters Lu's territory in Jianglou, with the celestial mark at xu. Beyond 4° 24′ 33″ in Stomach the sun enters Zhao's territory in Daliang, with the celestial mark at you.
63
Beyond 7° 96′ 20″ in Net the sun enters Jin's territory in Shichen, with the celestial mark at shen. Beyond 9° 47′ 10″ in Well the sun enters Qin's territory in Chunshou, with the celestial mark at wei. Beyond 4° 95′ 26″ in Willow the sun enters Zhou's territory in Chunhuo, with the celestial mark at wu.
64
Beyond 15° 56′ 35″ in Extended Net the sun enters Chu's territory in Chunwei, with the celestial mark at si. Beyond 10° 44′ 5″ in Axletree the sun enters Zheng's territory in Shouxing, with the celestial mark at chen. Beyond 1° 77′ 77″ in Base the sun enters Song's territory in Great Fire, with the celestial mark at mao.
65
Beyond 3° 97′ 72″ in Tail the sun enters Yan's territory in Splintered Wood, with the celestial mark at yin. Beyond 4° 36′ 66″ in Dipper the sun enters Wu-Yue's territory in Star Chronicle, with the celestial mark at chou. Beyond 2° 91′ 91″ in Girl the sun enters Qi's territory in Dark Emblem, with the celestial mark at zi.
66
To find the time of palace entry.
67
宿
For each, set the palace-entry lodge degrees and parts-seconds and subtract that day's solar degree before dawn and at midnight, (Compute when within about one degree. Multiply the remainder's parts by the day unit, (Carry the seconds down and multiply them through as well.) for the dividend; use that day's solar motion parts as divisor; Divide the dividend by the divisor; obtain the quotient and find the time by the issuing-and-gathering procedure to obtain that day's time and parts-seconds of the sun's palace entry.
68
Stepwise computation: gnomon and water-clock. Mid-limit: 182 days 62 parts 18 seconds. Winter solstice beginning-limit and summer solstice end-limit: 62 days 20 parts. Summer solstice beginning-limit and winter solstice end-limit: 120 days 42 parts.
69
Yong'an winter-solstice gnomon-shadow constant: 1 zhang 2 chi 8 cun 3 fen. Yong'an summer-solstice gnomon-shadow constant: 1 chi 5 cun 6 fen. Zhou divisor: 1428. Inner-outer divisor: 10,896.
70
Half-divisor: 2615. Three-fourths of the day unit: 3922½. One-fourth of the day unit: 1307½. Twilight parts: 130 parts 75 seconds.
71
Twilight notches: 2 notches 156 parts 90 seconds. Quarter-hour divisor: 313 parts 80 seconds. Second divisor: 100. To find the accumulated mid-term interval at noon within a qi.
72
Set the major remainder of the sought day and the half-divisor, subtract the major and minor remainders of the qi entered, and obtain that day's noon interval within the qi; Add this to the mid-term accumulation of that qi to obtain that day's noon mid-accumulation. (Divide the minor remainder by the day unit to obtain reduced parts.) To find whether noon after the two solstices falls within the beginning or end limit.
73
Set the noon mid-accumulation and its parts; if equal to or below the mid-limit, it is after the winter solstice; if above, subtract the mid-limit to obtain the interval after the summer solstice. Within each post-solstice period, if equal to or below the beginning-limit, it falls in the beginning-limit; if above, subtract the mid-limit in reverse, and the remainder is the entry into the end-limit. To find the fixed noon gnomon shadow length.
74
滿滿
For the beginning-limit after winter solstice and the end-limit after summer solstice, multiply the day's inner parts by one hundred and square them; set aside the product and divide by 1450; Add 50,308 to the result and combine with the halved limit parts; divide the assistant product to obtain parts, convert ten parts to one cun and ten cun to one chi, subtract from the central-earth winter-solstice gnomon-shadow constant, and the fixed gnomon shadow length sought is obtained.
75
滿滿
For the beginning-limit after summer solstice and the end-limit after winter solstice, multiply the day's inner parts by one hundred and square them for the upper term; Set the entry-limit parts below, multiply by 225 and reduce by one hundred, add 198,075 to obtain the divisor; (On either side of summer solstice when above the half-limit, subtract the half-limit and place the result in the upper position; set the half-limit below; for each, multiply inner parts by one hundred, subtract first and multiply second, divide by 7700, and add the result to the divisor.) Divide the upper term by the divisor to obtain parts, convert ten parts to one cun and ten cun to one chi, add to the central-earth summer-solstice gnomon-shadow constant, and the fixed gnomon shadow length sought is obtained.
76
To find the gnomon shadow at each quarter of the realm.
77
At each place measure the gnomon lengths at the winter and summer solstices and subtract them; the remainder is that place's solstitial gnomon difference; Subtract the central-earth solstitial gnomon lengths likewise to obtain the central-earth solstitial gnomon difference. When the sought day falls in the beginning-limit after winter solstice or the end-limit after summer solstice, if equal to or below the half-limit, double it; if above the half-limit, subtract the full limit in reverse and double the remainder as well; Add the days within the limit, multiply by three, and halve; take days as parts and ten parts as one cun, subtract from the central-earth solstitial gnomon difference to obtain the divisor; Set the central-earth winter-solstice gnomon-shadow constant, subtract the fixed central-earth gnomon shadow for the sought day, and multiply the remainder by that place's solstitial gnomon difference for the dividend; Divide the dividend by the divisor; subtract the result from that place's winter-solstice gnomon length to obtain the fixed gnomon shadow for that place on that day. When the sought day falls in the beginning-limit after summer solstice or the end-limit after winter solstice, if equal to or below the half-limit, double it; if above the half-limit, subtract the full limit in reverse and double the remainder as well; Add the days within the limit, multiply by three, and divide by four; take days as parts and ten parts as one cun, add to the central-earth solstitial gnomon difference to obtain the divisor; Set the fixed central-earth gnomon shadow for the sought day, subtract the central-earth summer-solstice gnomon-shadow constant, and multiply the remainder by that place's solstitial gnomon difference for the dividend; Divide the dividend by the divisor; add the result to that place's summer-solstice gnomon length to obtain the fixed gnomon shadow for that place on that day.
78
Ascent-descent and sunrise parts for the twenty-four solar terms. (The tables below are omitted.) Ascent-descent rates before and after the equinoxes.
79
Three days before the spring equinox the sun enters within the equator, and three days after the autumn equinox it exits beyond the equator; therefore its ascent and descent do not match other days, and separate numbers are now established and used for each.
80
Awakening of Insects: on the twelfth day, ascend four. (67, 16.) This is the terminal rate; its use ends here. (The subtractive correction also stops here.)
81
On the thirteenth day, ascend four. (41, 6.) On the fourteenth day, ascend four. (38, 90.) On the fifteenth day, ascend four.
82
Autumn Equinox: on the first day, descend four. (38.) On the first day, descend four. (39.) On the second day, descend four. (59.) On the third day, descend four. (68.) This is the initial rate; its use begins here. (The additive correction also begins here.)
83
To find each day's sunrise, sunset, dawn, dusk, and half-day parts.
84
For each term, apply the initial ascent-descent rate—subtract when ascending and add when descending—to the first day's sunrise parts of that qi to obtain the sunrise parts below day one; with the increase-decrease difference (still apply the additive-subtractive correction.) Increase or decrease the ascent-descent rates and apply them in sequential accumulation to obtain each day's sunrise parts; subtract in reverse from the day unit to obtain the sunset parts; subtract sunrise parts from sunset parts and halve the result for the half-day parts; subtract twilight parts from sunrise parts to obtain dawn parts; add sunset parts to obtain dusk parts.
85
To find the double-hours and quarter-hours of sunrise and sunset.
86
滿 滿
Set the sunrise-sunset parts, multiply by six, and divide by the double-hour divisor to obtain the double-hour count; with the remainder, divide by the quarter-hour divisor to obtain quarter-hours, and what does not fill becomes parts. Count from midnight beyond the counting rod to obtain the result sought. To find the day and night quarter-hours.
87
滿 退 退
Set the sunrise parts, multiply by twelve, and divide by the quarter-hour divisor to obtain quarter-hours and parts as the night quarter-hours; subtract in reverse from one hundred; the remainder is the day quarter-hours and parts-seconds. To find watch and point rates: set the dawn parts, multiply by four, and shift one place to obtain the watch rate; Multiply the watch rate by two and shift one place to obtain the point rate.
88
To find the double-hour and quarter-hour of a watch or point.
89
滿 滿 滿
Set the watch-point rate, multiply by the sought number of watches or points and again by six, add the watch tally quarter-hours within, and divide by the double-hour divisor to obtain the double-hour count; with the remainder, divide by the quarter-hour divisor to obtain the quarter-hour count; what does not fill becomes parts; count from that day's double-hour and quarter-hour beyond the counting rod to obtain the result sought.
90
To find the clepsydra quarter-hours at each quarter of the realm.
91
退
At each place set the water clepsydra running and fix the winter- or summer-solstice night quarter-hours there; subtract from fifty quarter-hours, and the remainder is the solstitial difference in quarter-hours. Set the ecliptic's degrees and parts north or south of the equator for the sought day, multiply by the solstitial-difference quarter-hours, advance one place, and divide by 239 to obtain quarter-hours; with the remainder, multiply by the quarter-hour divisor and divide down to obtain parts; subtract within and add without to fifty quarter-hours to obtain the sought day and night quarter-hours; subtract from one hundred quarter-hours; the remainder is the day quarter-hours. (The double-hours and quarter-hours of sunrise and sunset, watch and point difference rates, and the like are all found by the methods above.)
92
To find the ecliptic degrees north or south of the equator.
93
滿退
Set the sunrise parts; if they reach one-quarter of the day unit or more, discard that amount; the remainder is the outer parts; If below one-quarter of the day unit, subtract in reverse; the remainder is the inner parts. Set the inner or outer parts, multiply by one thousand, and divide by the inner-outer divisor to obtain degrees; with the remainder, divide down for parts and seconds; this is the ecliptic's degrees north or south of the equator; Subtract within and add without to the quadrant limit to obtain the ecliptic's degrees from the pole.
94
To find the degrees from the meridian and the watch-interval difference.
95
退
Set the half-divisor, subtract the dawn parts, and the remainder is the distance-from-mid parts; Multiply by one hundred and divide by the Zhou divisor to obtain the degrees from the meridian; Subtract this from 183 degrees 12 parts 83½ seconds, multiply the remainder by four, shift one place, and obtain the watch-interval difference per watch. To find the culminating stars at dusk, dawn, and the five watches.
96
宿 滿宿
Set the degrees from the meridian, add that day's noon equatorial solar degree and count in lodges; the lodge reached is the culminating star at dusk and the first watch; Add the watch-interval difference cumulatively; when it fills the equatorial lodge sequence, discard the quotient; the culminating stars for each successive watch and at dawn are thereby obtained. Procedure for lunar motion.
97
Revolution cycle parts: 144,110, seconds 6,020, micro-units 60. Revolution cycle days: 27, remainder 2,900, seconds 6,020, micro-units 60. Revolution mid-cycle days: 13, remainder 4,065, seconds 3,010, micro-units 30.
98
New-moon difference: 1 day, remainder 5,104 parts, seconds 3,979, micro-units 40. Quarter-moon divisor: 7 days, remainder 2,001 parts, seconds 2,500. Second divisor: 10,000. Micro divisor: 100.
99
First-quarter arc: 91 degrees 31 parts 41 seconds (large) Full-moon arc: 182 degrees 62 parts 83½ seconds. Last-quarter arc: 273 degrees 94 parts 25 seconds (small) Moon mean daily motion: 13 degrees 36 parts 87½ seconds.
100
Parts-seconds divisor: 100. Seven-day initial count: 4,648; final count: 582. Fourteen-day initial count: 4,065; final count: 1,165. Twenty-one-day initial count: 3,483; final count: 1,747.
101
仿
Twenty-eight-day initial count: 2,901. To find the mean new moon, quarter moon, and full moon at their entry into revolution. (Whenever seconds are given, micro-units follow; other cases follow this rule.)
102
滿
Set the civil-year new-moon accumulated parts, cast out the revolution cycle parts and seconds, divide the remainder by the day unit to obtain days, with the unfilled portion as remainder-seconds; this yields the day and remainder-seconds of entry into revolution for the mean new moon of the eleventh month of the civil year; Add the quarter-moon divisor cumulatively, cast out and name as before, and obtain the day-and-hour entry into revolution with remainder-seconds for each quarter and full moon; To find directly the next new moon's entry into revolution, add the new-moon difference. (Apply the inner difference to add or subtract, and obtain the entry into revolution with remainder-seconds for the mid-term new moon, quarter moon, and full moon.)
103
To find the revolution fixed parts and accumulated waning-waxing degrees. (Table below omitted.) To find the fixed waning-waxing number for the mid-term new moon, quarter moon, and full moon at entry into revolution.
104
Set the entry-into-revolution minor remainder, multiply by the deficit-surplus rate beyond the count for that day, and divide by the day unit; apply the result to the waning-waxing accumulation to obtain the fixed number. On the fourth and seventh days and below in remainder: if below the initial count, multiply by the initial rate and divide by the initial count, and apply the result to the waning-waxing accumulation for the fixed number; If at or above the initial count, subtract the initial count; multiply the remainder by the final rate and divide by the final count, subtract from the initial rate, and take the remainder as the waning-waxing accumulation for the fixed number. On the fourteenth day and below in remainder: if at or above the initial count, subtract the initial count; multiply the remainder by the final rate and divide by the final count to obtain the waning-waxing fixed number.
105
To find the mid-day of the new moon, quarter moon, and full moon.
106
退 滿退 西
Taking Xanadu as the standard, set the distance in li, multiply by 4,359, shift one place, and reduce by ten thousand to obtain parts, called the inner difference; Add or subtract this from the mean new moon, quarter moon, and full moon minor remainders; on fullness or shortfall, advance or retreat the major remainder to obtain the mid-term new moon, quarter moon, and full moon day and remainder. (Add for places to the east and subtract for places to the west.)
107
To find the fixed new moon, quarter moon, and full moon days.
108
滿退 退 退 退 退 退使
Set the mid-term new moon, quarter moon, and full moon minor remainders, subtract waning and add waxing, then add the entry-into-qi and entry-into-revolution waning-waxing fixed number; on fullness or shortfall, advance or retreat the major remainder and count from renxu beyond the counting rod; each fixed new moon, quarter moon, and full moon with its day, double-hour, and remainder is thereby obtained. When the stem of the fixed new moon matches that of the following new moon, the month is long; when they differ, the month is short; a month with no mid-qi within it is intercalary. Inspect the fixed new moon minor remainder: after the autumn equinox, if it reaches three-quarters of the day unit or above, advance one day; After the spring equinox, subtract the spring-equinox sunrise parts from the fixed-new-moon sunrise parts, divide the remainder by three, and subtract that from three-quarters of the day unit; if the fixed new moon minor remainder reaches this number of parts or above, advance one day as well; if there is a crossing and first contact comes before sunset, do not advance. When the fixed quarter or full moon minor remainder falls below the sunrise parts, retreat one day; if there is a crossing and first contact comes before sunrise, retreat even when the minor remainder lies after sunrise. For a full moon on the seventeenth day, also inspect whether the fixed new moon minor remainder lies at or below three-quarters, (After the spring equinox apply the subtracted fixed number.) compare it with the fixed full moon minor remainder at or above the sunrise parts; if the new moon is less and the full moon greater, do not retreat the full moon but still advance the new moon; if the full moon is less and the new moon greater, do not advance the new moon but still retreat the full moon. (The motions of the sun and moon have expansion and contraction, fast and slow; and the numbers added or subtracted may yield four long months and three short. (When proceeding routinely one should inspect whether the time-of-day is early or late and advance or retreat according to what is nearer, so as not to exceed four long and three short.)
109
To find the mid-accumulation for the fixed new moon, quarter moon, and full moon.
110
退
Set the fixed new moon, quarter moon, and full moon minor remainders and subtract the mid-term new moon, quarter moon, and full moon minor remainders; use the remainder to add or subtract from the mean day-remainder of entry into a qi for the new moon, quarter moon, and full moon, (for the mid-term new moon, quarter moon, and full moon, add if less and subtract if greater.) this is the fixed new moon, quarter moon, and full moon at their entry into a qi; add this to the mid-term accumulation of that qi to obtain the mid-accumulation for the fixed new moon, quarter moon, and full moon. (with the remainder, divide down by the day unit to obtain parts and seconds.)
111
To find the solar degrees at the time-of-day for the fixed new moon, quarter moon, and full moon.
112
宿宿
Set the reduced remainder for the fixed new moon, quarter moon, and full moon and multiply by the increase-decrease rate for the day of the qi entered, (the increase-decrease of expansion and contraction.) reduce by ten thousand and apply to the expansion-contraction accumulation below; then add when in expansion and subtract when in contraction from the mid-accumulation of the fixed new moon, quarter moon, and full moon; add the ecliptic lodge and degree of the sun's motion at the winter solstice with time-of-day; discard full lodges; the degrees, parts, and seconds of the sun at the time-of-day for each fixed new moon, quarter moon, and full moon are thereby obtained.
113
滿滿宿
Alternate method: set the reduced remainder for the fixed new moon, quarter moon, and full moon and set aside a copy; multiply by that day's increase-decrease rate for expansion and contraction and reduce by ten thousand; when increase is called for, add in expansion and subtract in contraction, and when decrease is called for, subtract in expansion and add in contraction; when the copy fills 100 convert to parts and when parts fill 100 convert to degrees; add to that day's midnight solar degree and count in lodges; each yields the ecliptic lodge of the sun's motion at the time-of-day for that day. (If each day's midnight solar degree has already been entered in the calendar, this method is especially effective.)
114
To find the lunar degrees at the time-of-day for the fixed new moon, quarter moon, and full moon.
115
宿
Whenever at conjunction the sun and moon share the same degree at the time-of-day, the ecliptic solar degree at the fixed new moon with time-of-day is the ecliptic lunar degree at the fixed new moon with time-of-day; For the quarter and full moons, add the quarter-moon or full-moon arc to the ecliptic solar degree at the fixed event with time-of-day and discard full lodges; the ecliptic lunar degree with parts and seconds at the fixed new moon, quarter moon, and full moon with time-of-day is thereby obtained.
116
To find entry into revolution at midnight and noon.
117
退滿
Set the mid-term new moon's entry into revolution and subtract the mid-term new moon minor remainder to obtain entry into revolution at midnight for the mid-term new moon. Subtract the mid-term new moon minor remainder from the half-divisor and use the remainder to add or subtract from the mid-term new moon's entry into revolution at the time-of-day, (if the mid-term new moon remainder is less than the half-divisor, add; (if greater than the half-divisor, subtract.) this is entry into revolution at noon for the mid-term new moon. If the fixed new moon major remainder has been advanced or retreated, adjust the revolution day as well; otherwise take the mid-term value as fixed; add one day cumulatively each day; when it fills the revolution cycle day and remainder-seconds, cast out and name as before; entry into revolution at midnight and noon for each day is thereby obtained. (To find midnight, accumulate entry into revolution from the fixed new moon at midnight; to find noon, accumulate from the fixed new moon entry into revolution at noon; (to find entry into revolution at the time-of-day, use the method for finding entry into qi at the time-of-day.)
118
To find the lunar degrees at the time-of-day and at midnight.
119
滿
Set that day's entry into revolution beyond the count and its fixed revolution parts, multiply by the fixed new moon, quarter moon, or full moon minor remainder, divide by the day unit, and obtain the revolution parts at the time-of-day; (when parts fill one hundred, they become degrees.) Subtract the fixed-event lunar degree at the time-of-day to obtain the midnight lunar degree. Add the successive fixed revolution parts cumulatively to obtain the midnight lunar degree for each day. (Whether from new moon to quarter or full moon, or to the following new moon, one may accumulate; but when near the difference is small and when far it is large. Set the lunar degrees between the sought midnight and the preceding or following midnight as the motion arc, compute the accumulated entry-into-revolution degrees between those days, subtract the motion arc, divide the remainder by the number of intervening days, and obtain the daily motion difference. When the day-difference is large, add the daily motion from fixed revolution parts; when small, subtract the daily fixed revolution parts; that suffices. For speed, use this figure. (For finer detail, use the procedure below.)
120
To find the lunar degrees at dawn and dusk.
121
宿
Set that day's dawn parts, multiply by that day's fixed revolution parts beyond the count, divide by the day unit, and obtain the dawn revolution parts; subtract these from the fixed revolution parts; the remainder is the dusk revolution parts. Multiply the fixed revolution parts by the fixed minor remainder of the new or full moon, divide by the day unit to obtain the time-of-day parts, subtract from the dawn or dusk revolution parts for the before case; if insufficient, subtract in reverse for the after case; then add before and subtract after from the lunar degree at the time-of-day to obtain the lodge, degrees, parts, and seconds of the dawn or dusk lunar position.
122
To find the fixed dawn and dusk intervals for the new moon, quarter moon, and full moon.
123
For each, subtract the first-quarter dusk fixed moon from the new-moon dusk fixed moon; the remainder is the fixed dusk interval after the new moon. Subtract the full-moon dusk fixed moon from the first-quarter dusk fixed moon; the remainder is the fixed dusk interval after the first quarter. Subtract the last-quarter dawn fixed moon from the full-moon dawn fixed moon; the remainder is the fixed dawn interval after the full moon. Subtract the next new moon's dawn fixed moon from the last-quarter dawn fixed moon; the remainder is the fixed dawn interval after the last quarter.
124
To find the daily fixed revolution degrees.
125
滿宿
Accumulate the entry-into-revolution degrees under each fixed interval between the days, subtract the dawn or dusk fixed interval, divide the remainder by the number of intervening days, and obtain the day-difference; (if the fixed interval is greater, add; (if less, subtract.) add or subtract this from each day's fixed revolution parts to obtain the fixed revolution degrees; Starting from the dawn or dusk moon at the new moon, quarter moon, or full moon, add cumulatively each day, cast out full lodges, and obtain the dawn or dusk lunar degree with parts and seconds for each day. (In calendar annotation, record the dusk moon from the new-moon day onward and the dawn moon from the day after the full moon.) Earlier calendars included nine-path lunar monthly degrees; though the figures are numerous and hard to omit, the procedure is set forth below.
126
To find the day and double-hour of true crossing.
127
滿
Set the crossing cycle day and remainder-seconds and subtract the general day and remainder-seconds of entry into crossing at the month's mean new moon with time-of-day; the remainder is the day count and remainder-seconds after the mean new moon with time-of-day at which mean crossing occurs; (the same for the mid-term new moon.) Add the month's mid-term new moon major and minor remainders; count the major remainder from renxu beyond the counting rod to obtain the day, double-hour, and remainder-seconds of mean crossing. (To find the next crossing, add the crossing cycle day and remainder-seconds; if the major remainder fills the era unit, cast it out and count as before to obtain the next mean-crossing day, double-hour, and remainder-seconds.)
128
To find the waning-waxing fixed number for mean crossing's entry into revolution.
129
Set the mean-crossing minor remainder, add midnight entry into revolution for that day, multiply the remainder by that day's increase-decrease rate, divide by the day unit, and apply the result to increase or decrease the waning-waxing accumulation below that day to obtain the fixed number. To find the day and double-hour of mean crossing.
130
滿退
Set the mean-crossing minor remainder, apply the waning-waxing fixed number for mean crossing's entry into revolution (subtract when waning, add when waxing), and on fullness or shortfall advance or retreat the day and double-hour to obtain the true-crossing day, double-hour, and remainder-seconds; compare with the fixed new moon day and double-hour to obtain the month and day. To find the mid-accumulation at the mid-term new moon with time-of-day.
131
退
For each, add the day and remainder of entry into a qi at the month's mid-term new moon with time-of-day to the mid-accumulation and remainder of that qi; count the days as degrees, divide the remainder down by the day unit into parts and seconds, and obtain the mid-accumulation in degrees, parts, and seconds at the mid-term new moon with time-of-day. To find the ecliptic lunar degree at true crossing with time-of-day.
132
滿退宿
Set the day count and remainder-seconds after mean crossing at the mid-term new moon with time-of-day, convert the remainder within the day through the day unit advancing two places, take 39,121 as the divisor for degrees, divide down the remainder into parts and seconds, add to the mid-accumulation at the mid-term new moon with time-of-day, then add and count from the ecliptic solar degree at the winter solstice with time-of-day to obtain the ecliptic lodge, degree, parts, and seconds of the moon's departure at true crossing with time-of-day for that month. To find the next crossing, add the crossing mid-arc in degrees, parts, and seconds and count in lodges to obtain the result.
133
宿
To find the accumulated ecliptic lodge degrees.
134
宿宿 宿宿 宿
Set the full ecliptic lodge degree at true crossing with time-of-day and subtract the ecliptic lodge degree, parts, and seconds of the moon's departure; the remainder is the degrees and parts-seconds after the distance; add the ecliptic lodge degrees cumulatively to obtain the accumulated ecliptic lodge degrees and parts-seconds after each true crossing. To find entry into the initial or final limit for accumulated ecliptic lodge degrees.
135
宿滿
Set the accumulated ecliptic lodge degrees and parts-seconds, cast out full crossing-image degrees and parts-seconds; if the remainder is at or below half the crossing image, it is the initial limit; if above, subtract the crossing-image degrees; the remainder is the final limit. (Entry-crossing accumulation degrees and crossing-image degrees are both in the Crossing Conjunctions chapter.)
136
宿
To find the lodge degrees of the moon's nine paths.
137
宿 宿 宿 宿西 宿西 宿 宿 宿西 宿 宿 宿 宿 退滿
Whenever the moon crosses, in winter it enters the yin calendar and in summer the yang calendar, and the moon moves on the green path; (After the winter and summer solstices, the green path's half-crossing lies at the lodge of the spring equinox, east of the ecliptic; after Start of Winter and Start of Summer, the green path's half-crossing lies at the lodge of Start of Spring, southeast of the ecliptic; at the opposed lodge it is likewise. (This should be worked out in detail.) In winter it enters the yang calendar and in summer the yin calendar, and the moon moves on the white path; (After the winter and summer solstices, the white path's half-crossing lies at the lodge of the autumn equinox, west of the ecliptic; after Start of Winter and Start of Summer, the white path's half-crossing lies at the lodge of Start of Autumn, northwest of the ecliptic; (at the opposed lodge it is likewise.) In spring it enters the yang calendar and in autumn the yin calendar, and the moon moves on the vermilion path; (After the spring and autumn equinoxes, the vermilion path's half-crossing lies at the lodge of the summer solstice, south of the ecliptic; after Start of Spring and Start of Autumn, the vermilion path's half-crossing lies at the lodge of Start of Summer, southwest of the ecliptic; (at the opposed lodge it is likewise.) In spring it enters the yin calendar and in autumn the yang calendar, and the moon moves on the black path. (After the spring and autumn equinoxes, the black path's half-crossing lies at the lodge of the winter solstice, north of the ecliptic; after Start of Spring and Start of Autumn, the black path's half-crossing lies at the lodge of Start of Winter, northeast of the ecliptic; (at the opposed lodge it is likewise.) The four seasons divide into eight nodes; where yin and yang cross, all meet the ecliptic; hence the moon has nine paths. For each, take the entered initial or final limit in degrees and parts, subtract 101 degrees, multiply the remainder by the degrees and parts of entry into the initial limit within the initial or final limit, halve and shift one place for parts, convert parts filling 100 to degrees, and name the result the general difference between the lunar path and the ecliptic.
138
宿宿 宿宿 宿宿 宿
For the sun, within the equator is yin and without is yang; for the moon, within the ecliptic is yin and without is yang. Therefore at true lunar crossing, degrees within lodges after the summer solstice are same-name and those after the winter solstice are different-name. In the same-name case, set the general difference between the lunar motion and the ecliptic, multiply by nine and reduce by eight to obtain the fixed difference; after half-crossing and before true crossing, subtract the difference; after true crossing and before half-crossing, add the difference; (This addition and subtraction varies by six degrees, unlike the same-name difference at ecliptic-equator crossing; compared gradually it diverges and shifts with the crossing location.) Still multiply the fixed difference by the true-crossing degrees' distance from the autumn equinox and divide by the quadrant to obtain the fixed difference between the lunar path and the equator; what was added before becomes subtraction and what was subtracted becomes addition. In the different-name case, set the general difference between the lunar motion and the ecliptic, multiply by seven and reduce by eight to obtain the fixed difference; after half-crossing and before true crossing, add the difference; after true crossing and before half-crossing, subtract the difference; (This addition and subtraction of six degrees in and out is just like the difference of unlike names at the yellow-red intersection; if compared they gradually coincide, the shift varies irregularly with the location of the node.) Again multiply the fixed difference by the true-crossing degrees' distance from the spring equinox and divide by the quadrant limit; the result is the fixed difference between the lunar path and the equator; what was previously added becomes subtraction and what was subtracted becomes addition; add or subtract each from the accumulated ecliptic lodge degrees to obtain the accumulated nine-path lodge degrees; subtract the previous lodge's accumulated nine-path degrees to obtain that lodge's nine-path degrees and parts-seconds. (The parts are rounded to the nearest large, half, or small degree; for spring, summer, autumn, and winter, the lodge degrees where the sun stands in each season serve as the standard.)
139
宿
To find the nine-path lodge degree of the moon's departure at true conjunction with time-of-day.
140
退滿 宿
Subtract 101 degrees from the ecliptic solar degree and parts at true conjunction with time-of-day; multiply the remainder by the true-crossing degrees and parts, halve and shift down for parts, and when parts fill 100 convert to degrees; this is called the general difference between the lunar path and the ecliptic. When of like name, set the lunar motion and ecliptic general difference, multiply by nine and reduce by eight to obtain the fixed difference, and add it; Again multiply the fixed difference by the true-crossing degrees' distance from the autumn equinox and divide by the quadrant limit; the result is the fixed difference between the lunar path and the equator, and subtract it. When of unlike name, set the lunar motion and ecliptic general difference, multiply by seven and reduce by eight to obtain the fixed difference, and subtract it; Again multiply the fixed difference by the true-crossing degrees' distance from the spring equinox and divide by the quadrant limit; the result is the fixed difference between the lunar path and the equator, and add it. Set the ecliptic lunar degree and parts at true conjunction with time-of-day, add or subtract the two differences, and the nine-path lodge degree and parts of the moon's departure at true conjunction with time-of-day are obtained.
141
To find the degree occupied by the moon at the true new moon, quarter moon, and full moon with time-of-day.
142
宿宿 宿滿宿宿
Set the ecliptic lodge position of the sun at the true new moon with time-of-day; whenever it is conjunction with time-of-day, the moon moves hidden beneath the sun at the same degree, and this is the lodge position of the moon's departure at that hour; For each, add the quarter- or full-moon degrees and parts-seconds to the ecliptic solar degree at the corresponding quarter or full moon with time-of-day, discard full lodges as before, and the ecliptic lodge, degrees, and parts-seconds occupied by the moon at each true new moon, quarter moon, and full moon with time-of-day are thereby obtained.
143
To find the nine-path lunar degree at the true new moon, quarter moon, and full moon with time-of-day.
144
宿宿 宿宿 宿
For each, add the moon's departure ecliptic lodge degrees and parts-seconds at the true new moon, quarter moon, or full moon with time-of-day to the accumulated ecliptic degrees after true crossing at the previous lodge, obtaining the accumulated ecliptic degrees after true crossing at that hour; as before, find the nine-path accumulated degrees and subtract the previous lodge's accumulated nine-path degrees; the remainder is the nine-path lodge, degrees, and parts-seconds of the moon's departure at the true new moon, quarter moon, or full moon with time-of-day. (At conjunction with time-of-day, if it is not true crossing, the sun is on the ecliptic and the moon on the nine paths; the lodges entered may differ in degree, but examine the two poles as if by a plumb line. Hence it is said that the moon moves hidden beneath the sun at the same degree, and that is the time-of-day. (For nine-path lunar degrees, find the lunar degrees at dawn, dusk, and midnight by the same methods as above.)
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